Long before "Seinfeld," there was "Einstein on the Beach" - the original show about nothing.

Director Robert Wilson's and composer Philip Glass' 1976 multimedia theatrical epic steamed into Berkeley's Zellerbach Hall on Friday night in all its steely, exuberant, brilliant, boring splendor, sponsored by Cal Performances. This was the first time the piece had been presented on the West Coast - part of a touring production that marks the first revival of "Einstein" in 20 years - and there was a whiff of the historic about the occasion.

And if the above description sounds self-contradictory, that is surely part of the creators' master plan. "Einstein" is at once urgent and aloof, frenzied and glacial, magical and maddening. Whatever reactions you have at any given moment are apt to be overturned the next.

"Einstein" is billed as an opera, but that seems like a needlessly limiting descriptor. In performance, the piece plays more like some kind of postmodernist vaudeville - a mostly disconnected series of expansive tableaux that leave the audience uncertain of what's coming around the next bend.

Most of the scenes are devoted to the obsessive playing out of a single theatrical-visual image - the arrival of a large locomotive, or the gathering of a crowd around a brick building - with music to match. But there are also long dance sequences (with choreography by Lucinda Childs), musical numbers, and the whimsical, inscrutable "knee plays" featuring the charismatic performers Helga Davis and Kate Moran, which serve as palate-cleansing interludes between the major scenes.

Famously, "Einstein" runs nearly 4 1/2 hours without an intermission, but the audience is free to come and go as the piece unfolds - a license that many in Friday's audience took with relief. There's something liberating in the knowledge that a performance doesn't need your presence to exist, not unlike the realization that you can safely take your eyes off the road when you're in the passenger seat of a car.

That sense of the performance's independence is established from the first moments, since things seem to be already in progress when the audience enters the hall. A low musical drone fills the auditorium, and Davies and Moran are already in place - brightly lit in their white shirts and suspenders - softly reciting the lists of numbers and disconnected bits of prose that will serve as the main verbal fodder of the piece. The actual beginning is marked by the moment when the audience collectively decides to quiet down.

From then on, the evening is devoted to stage images and processes that don't exactly mean anything - yet flirt just enough with the referential to keep you on your toes. The arrival of the 19th century train at the beginning is matched by a mysterious Greyhound bus several hours later. A pair of bewigged judges presides over not one but two court trials. A couple (possibly Einstein and his wife) take a nocturnal train ride that ends with a surprisingly dramatic denouement.

Words in "Einstein" are either flat-out empty - most of Glass' taut, luscious choral music is a setting of numbers and solfege syllables - or tauntingly absurd. Einstein is occasionally present as a violinist (the brisk and virtuosic Jennifer Koh, bewigged in a shaggy gray mop), or as a scientist frantically scribbling equations on an invisible blackboard.

What binds the evening together is the reliance throughout on extended repetition, combined with transitions in perspective that are achingly subtle. This is the M.O. that Wilson and Glass share, and one that they pursued in different ways in the years following "Einstein."

For Glass, the "Einstein" score - by turns manic and serene - offered a way to translate the process-based music he'd been writing throughout the early 1970s to a theatrical context. It opened up a slew of nearly two dozen operas in the decades to follow, many of which - especially "Satyagraha" and "Akhnaten," which completed his so-called "Portrait Trilogy" - found more traditionally dramatic uses for these discoveries.

But the "Einstein" score - conducted with expert clarity by Michael Riesman - is still all about the use of gradually shifting patterns that unfold over long periods of time (Andrew Sterman's wailing, soulful tenor saxophone solo during the "Building" scene feels like a dispatch from an entirely different cosmos). And Wilson's fondness for the slow fade - in "Night Train," for instance, the moon goes from crescent to full at a snail's pace - offers a visual correlative.

All of which, I suspect, brings us back to Einstein. Sitting through the endless repetitive rituals of each scene in "Einstein" makes time feel malleable in something like the way its title character first explored (the reference is made explicit in the final "Spaceship" scene, which features two Einsteins in glass cases, each one with a clock and moving at perpendicular angles to one another). In this performance, an hour feels like a minute, a minute like an hour.

That in turn lends a certain poignancy to the choral texts, with their endless chants of one-two-three-four one-two-three. Those words aren't just there to keep referential content at bay - though they're good for that too - but to try to retain some kind of structure, some kind of mathematical stability, in a world where everything is relative.